You are badly misinformed about what "right to work" is. In a union shop, the unionized "coerce" all employees in their bargaining units to participate, even in "right to work" states! Everyone is covered by the same contract! That's the whole point! Even in "right to work" states, everyone in the unit is coerced into participation by your understanding.
The only thing "right to work" offers is that people covered by the contract may choose not to pay dues (or choose to forgo some portion of the dues).
In all cases, all relevant employees are "coerced" into the union contract.